Synthesis of 4A molecular sieves from titanium-containing electric furnace molten slag and their adsorption properties

4A molecular sieves were successfully synthesized from the leaching solutions of fused titanium-containing electric furnace molten slag by using the reflux method and the hydrothermal method,respectively. The effects of H₂O/Na₂O mole ratio,reaction time,and temperature on the crystal phase and microstructure of 4A molecular sieves were systematically investigated when keeping the SiO₂/Al₂O₃ mole ratio at 2. It is indicated that a 4A molecular sieve with well crystallinity and uniform size can be obtained by using the reflux method when the H₂O/Na₂O mole ratio is controlled at 80 and the reaction time is 8 h. Meanwhile,by using the hydrothermal method,a 4A molecular sieve can also be successfully prepared when the reaction is controlled at 120℃ only for 3 h. The adsorption properties for Cu²⁺ by 4A molecular sieves obtained at different temperatures were studied. The optimum adsorption efficiency of 70% is gained for a 4A molecular sieve synthesized at 120℃ for 150 min.